BISAZO DYES BASED ON HYDROXYNAPHTHALENECARBOXYLIC ACID

摘要

Disclosed are bisazo compounds of the formula Ia or Ib where RSUP1 /SUPis hydrogen or methyl, the X groups are independently -CHSUB2/SUBCHSUB2/SUB- or -CHSUB2/SUBCHSUB2/SUBCHSUB2/SUB-, RSUP2/SUP, RSUP3/SUP, and RSUP4 /SUPare independently hydrogen or methyl, A is an anion and n corresponds to the valency of A. Also disclosed are the use of the bisazo compounds for dyeing, especially paper, and colorants containing said bisazo compounds.